title: Study of platelet aggregation in acute coronary syndrome with special reference to metabolic syndrome.
abstract: BACKGROUND
  Antiplatelet drug resistance increases the risk of adverse events like stent thrombosis in acute coronary syndrome (ACS). Metabolic syndrome (MS) is a prothrombotic state and presence of MS further increases the risk of antiplatelet drug resistance.
  
  
  OBJECTIVE
  We studied platelet aggregation characteristics in patients of ACS for aspirin or clopidogrel resistance. We studied the relation of drug resistance with blood markers like high sensitivity C-reactive protein (hsCRP). We also studied for any relation of drug resistance with presence of MS.
  
  
  METHODS
  We studied platelet aggregation characteristics by optical aggregometry using platelet-rich plasma (PRP) of patients. Collagen (2 μg/mL) and adenosine diphosphate (ADP; 10 μmol) were used. Greater than 50% aggregation in PRP of patients was taken as an evidence of drug resistance. Suitable blood tests were done including newer risk markers like hsCRP, apolipoprotein B, and fibrinogen.
  
  
  METHODS
  Statistical tests included Student's t-test and Kendall's rank correlation coefficient.
  
  
  RESULTS
  We had a total of 94 patients of ACS with 47 (50%) having MS. MS patients showed higher blood levels of hsCRP and fibrinogen. Twenty-eight (59.5%) patients with MS showed antiplatelet drug resistance compared to 12 patients without MS. Serum fibrinogen showed strongest correlation with drug resistance. HsCRP levels showed correlation with aspirin resistance (r = 0.53) only in the MS group.
  
  
  CONCLUSIONS
  We found significantly high prevalence of antiplatelet drug resistance. Aspirin and clopidogrel resistance was comparable. MS was a significant risk factor for drug resistance. The prothrombotic and proinflammatory markers showed strong correlation with drug resistance. A larger randomized trial is needed to better characterize this clinical problem.
authors.affiliation: Department of Medicine, Medical College, Kolkata, India.
authors.forename: Rudrajit
authors.initials: R
authors.lastname: Paul
authors.forename: Amit K
authors.initials: AK
authors.lastname: Banerjee
authors.forename: Shantanu
authors.initials: S
authors.lastname: Guha
authors.forename: Utpal
authors.initials: U
authors.lastname: Chaudhuri
authors.forename: Srabani
authors.initials: S
authors.lastname: Ghosh
authors.forename: Jayati
authors.initials: J
authors.lastname: Mondal
authors.forename: Ramtanu
authors.initials: R
authors.lastname: Bandyopadhyay
keywords: Aspirin resistance; clopidogrel resistance; fibrinogen; high sensitivity C-reactive protein; metabolic syndrome